Extension-ladder



QNQ Model.) 2 Sheets-,-Sheet' 1. I

T. Poss-m, EXTENSION LADDER.

4 No. 532,700. Patented Jan. 15, 1895.

MO 2 Sheets-Sheet 2..

T. POSSIN. EXTENSION LADDER.

No. 532,700. Patented Jan. 15, 1895.

Wiigzsses THE warns virus 00. wum'ou'mo wunma'rau, D. c.

.NrE-D STATES PATENT 01mins,

THEODOR POSSIN, OF ROANOKE, VIRGINIA.

EXTENSION-LADDER.

SPECIFICATION forming part of Letters Patent No. 532,700, dated January15, 1895.

Application filed April 23, 1894. Serial No. 508,691. (No model.)

To aZZ whom it may concern.-

in the county of Roanoke and State of Virginia, have invented a new anduseful Extenanon-Ladder, of which the following is a specification.

The invention relates to improvements in extension ladders.

The object of the present invention is to improve the construction ofextension ladders, and to prevent any liability of the extension sectionof the ladder accidentally falling in. event of the hoisting mechanismbeing tampered with and released.

A further object of the invention is to enable the extension sectioutobe' reversed, to counteract any tendency to warp, thereby preventinganyliability of its binding in the ways or guides of the lower or mainsection of the ladder; and another object of the invention is to providean adj ustable'shelfadapted to be arranged in ahorizontal position,irrespective of the inclination or position of the ladder.

- The invention consists in the construction and novel combination andarrangement of parts hereinafter fully described, illustrated in theaccompanying drawings andpointed out in the claims hereto appended.

In the drawings: Figure l is a perspective V1ew of an extension ladderconstructed in' accordance with this invention. Fig. 2 is a longitudinalsectional view, the ladder being 7 in an inclined position. Fig. 3 is asimilar view, the ladder being in a vertical position. Fig. 4 is adetail perspective view of one of the swinging catches. Fig. 5 is adetail of the lock for the winding drum.

Like numerals of reference indicate corresponding parts in all thefigures of the drawmgs.

1 designate a lower or main section of an extension ladder provided withguides 2, and having sliding therein an extension section 3. Eachsection of the ladder consists of suitable sides, and connectingtransverse rungs; and the guides, which form ways for the extensionsection, are substantially L-shaped, and are secured to the sides of thelower or main secion.

The extension section is hoisted by means of a rope or cable 4 passingover a pulley 5,

and having one end attached to one of the lower rungs of the extensionladder section 3, audits other end wound around a windlass shaft 6,journaled in suitable bearings of the lower or main section, and locateda suitable distance from the ground,'in order that a removable crankhandle 7 may be within easy reach. The pulley is arranged within asuitable block or bearing, and depends from the top rung of the lower ormain section, and by rotating the windlass shaft it will be readilyapparent that the extension section will be moved upward in the waysformed by the L- shaped guides. I

In order to prevent the windlass shaft from being tampered with andreleased, a cog wheel or ratchet 8 is arrangedon the outer face of oneof the sides of the lower or main section 1 of the ladder, and connectedwith the windlass shaft, and is arranged to be engaged by a notched bolt9 of a lock 10, which may be of any suitable construction, and which isoperated by a keyll. In the accompanying drawings only one shaft isemployed for winding the cable or. rope, but it will be readily '4apparent that with those windlasses employing two shafts and having cogwheels arranged adjacent to a side of the ladder, the lock may bearranged to engage one of those cogs without employing one especiallyfor this purpose.

The extension section is provided at each end with a swinging catch 12,which is approximately rectangular, being composed of similar sides 13,and a lower cross or connecting piece let. The swinging catch isprovided at the upper ends of its sides 13 with bearings 15, to receivethe rung, thereby forming an economic hinge; and at the bottom theswinging catch is provided with curved shoes 16 to engage the rungs ofthe main section 1. It will be seen that when the ladder is in aninclined position the swinging catch, hanging in a vertical position, isarranged to engage automatically the rungs of the loweror main section1, whereby should the lower section be tampered with and, the cable orrope rewith a rung. When it is desired to lower the extension section,the ladder is brought to a vertical position, as-illustrated in Fig. 3of the accompanying drawings, to carry the swinging catches away fromthe rungs of the lower or main section, to prevent the catches frominterfering with the downward movement of the extension section.

A shelf 17 is journaled between the sides of the extension section, andhas mounted or fixed on its journals 1S ratchet wheels 19, arrangedadjacent to the inner faces of the sides of the extension section, andadapted to be engaged by upper and lower pawls 20 and 21. A pair ofupper and lower pawls is pivoted to the inner face of each side of theextension section; and each pawl is arranged in a keeper 22. The shelfis adapted to be turned to bring it into a horizontal position to enableit to assu me that position, whatever may be the inclination of theextension ladder.

The shelf may be swung to either side of the extension section; and tocounteract warping, which would interfere with the free sliding of theextension section; the latter is made reversible by reason of a swingingcatch being arranged at each end of it. From time to time the extensionsection should be turned end for end, and also turned over to bring itsinner side'outward,and by this changing the position of the extensionsection, any tendency of the same to warp is prevented.

It will be seen that the ladder is simple and comparatively inexpensivein construction, that it is positive and reliable in its operation, andthat accidents due to the sudden ac cidental downward movement of theextension section are prevented.

It will also be apparent that the extension section is prevented fromwarping, and is thereby caused to move freely in the guides or ways, andthat the shelf may be readily arranged in a horizontal position. Thelock will prevent any tampering with the windlass, and the doublearrangement of pawls at each side or end of the shelf, enables thelatter to sustain a heavy weight.

Changes in the form, proportion and the minor details of constructionmay be resorted to without departing from the principle or sacrificingany of the advantages of this in- Vention.

hat I claim is- 1. In an extension ladder, the combination of a lower ormain section provided with ways, an extension section sliding in theways, a Windlass for hoisting the extension section, a cog wheelarranged on the lower or main section and connected with the Windlass,and a key operated lock havinga bolt arranged adjaeent to said cog wheeland interlocking with the teeth thereof, substantially as described.

2. In an extension ladder, the combination of a main section providedwith ways, a reversible extension section provided at each end with aswinging catch to engage the rungs of the main section,'and anadjustable and reversible shelf jourualed between the sides of theextension section,and arranged to swing through the spaces between itand the adjacent rungs, and provided with means for locking it in itsadjustment, substantially as described.

3. The combination with aladder provided with bearings, an adjustableshelf provided with journals arranged in the bearings, ratchet wheelsfixed to the journals, and pawls mounted on the ladder and engaging theratchet wheels, substantially as described.

In testimony that I claim the foregoing as my own I have hereto affixedmy signature in the presence of two witnesses.

THEODOR POSSIN.

Witnesses:

D. SAYLOR Goon, EVERETT PERKINS.

